title: The effect of head position on the distribution of topical nasal medication using the Mucosal Atomization Device: a cadaver study.
abstract: BACKGROUND
  The Mucosal Atomization Device (MAD) distributes medication throughout the paranasal sinuses for patients with chronic rhinosinusitis (CRS). Determining the optimal head position is important to ensure maximal delivery of medication to the sinus cavities. The objective of this work was to determine the effect of the lying-head-back (LHB) and head-down and forward (HDF) position, on the distribution of topical nasal medication via MAD in cadaver specimens.
  
  
  METHODS
  Twenty specimens having received complete functional endoscopic sinus dissection were chosen. The MAD was used to administer 2 mL of fluorescein-impregnated saline solution through the nose in both the LHB and HDF positions. Fluorescein was identified on 11 predetermined anatomical areas using a blue light filter. Three blinded investigators assessed endoscopic images to determine the presence of fluorescein.
  
  
  RESULTS
  A total of 440 anatomical locations (n = 20 cadavers) received administration of the fluorescein nasal spray in the LHB or HDF position. LHB position had significantly greater total distribution to all pertinent anatomical sites than the HDF position (76% vs 41%; p < 0.001; 95% confidence interval [CI], 0.26-0.44). The proportion of staining was significantly greater for the ethmoid (p = 0.11; 95% CI, 0.05-0.66), frontal (p < 0.01; 95% CI, 0.20-0.80), and sphenoid sinuses (p = 0.03; 95% CI, 0.07-0.73) when compared to the HDF position.
  
  
  CONCLUSIONS
  A greater distribution of medication to the sinonasal cavities was observed in the LHB position compared to the HDF position. These areas are of particular clinical relevance in postsurgical patients with refractory CRS.
authors.affiliation: Division of Otolaryngology, University of British Columbia, St. Paul's Sinus Centre, Vancouver, BC, Canada.
authors.forename: Al-Rahim R
authors.initials: AR
authors.lastname: Habib
authors.forename: Andrew
authors.initials: A
authors.lastname: Thamboo
authors.forename: Jamil
authors.initials: J
authors.lastname: Manji
authors.forename: Rachelle C
authors.initials: RC
authors.lastname: Dar Santos
authors.forename: Eng Cern
authors.initials: EC
authors.lastname: Gan
authors.forename: Amy
authors.initials: A
authors.lastname: Anstead
authors.forename: Amin R
authors.initials: AR
authors.lastname: Javer
mesh_terms: D000281:Administration, Intranasal / Q000379:methods*; D002102:Cadaver; D019793:Fluorescein; D005456:Fluorescent Dyes; D006257:Head / Q000502:physiology*; D006801:Humans; D009330:Nebulizers and Vaporizers; D010256:Paranasal Sinuses; D016896:Treatment Outcome
chemical_list: D005456:Fluorescent Dyes; D019793:Fluorescein
keywords: chronic rhinosinusitis; endoscopic sinus surgery; medical therapy; paranasal sinuses; sinusitis; topical therapy